EP0780704A3 - Plural frequency method and system for identifying metal objects in a background environment - Google Patents

Plural frequency method and system for identifying metal objects in a background environment Download PDF

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Publication number
EP0780704A3
EP0780704A3 EP96119190A EP96119190A EP0780704A3 EP 0780704 A3 EP0780704 A3 EP 0780704A3 EP 96119190 A EP96119190 A EP 96119190A EP 96119190 A EP96119190 A EP 96119190A EP 0780704 A3 EP0780704 A3 EP 0780704A3
Authority
EP
European Patent Office
Prior art keywords
background environment
metal objects
background
frequency method
plural frequency
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP96119190A
Other languages
German (de)
French (fr)
Other versions
EP0780704B1 (en
EP0780704A2 (en
Inventor
Donald K. Shoemaker
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Whites Electronics Inc
Original Assignee
Whites Electronics Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Whites Electronics Inc filed Critical Whites Electronics Inc
Publication of EP0780704A2 publication Critical patent/EP0780704A2/en
Publication of EP0780704A3 publication Critical patent/EP0780704A3/en
Application granted granted Critical
Publication of EP0780704B1 publication Critical patent/EP0780704B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V3/00—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation
    • G01V3/08—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices
    • G01V3/10—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices using induction coils
    • G01V3/104—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices using induction coils using several coupled or uncoupled coils

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Remote Sensing (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Electromagnetism (AREA)
  • Environmental & Geological Engineering (AREA)
  • Geology (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Geophysics (AREA)
  • Geophysics And Detection Of Objects (AREA)
  • Radar Systems Or Details Thereof (AREA)

Abstract

A system for detecting metal targets located in a background environment such as the ground evaluates metal targets by processing components of signals at two or more different frequencies. A component of the received signal induced by the ground can be eliminated by subtracting signal components measured at two different frequencies. The received signal can be processed to account for changes in the background response with frequency. The type of an unknown target can be identified by processing background excluded components to produce data characterizing the target type.
EP96119190A 1995-12-21 1996-11-29 Plural frequency method and system for identifying metal objects in a background environment Expired - Lifetime EP0780704B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US576009 1995-12-21
US08/576,009 US5654638A (en) 1995-12-21 1995-12-21 Plural Frequency method and system for identifying metal objects in a background environment

Publications (3)

Publication Number Publication Date
EP0780704A2 EP0780704A2 (en) 1997-06-25
EP0780704A3 true EP0780704A3 (en) 1998-01-28
EP0780704B1 EP0780704B1 (en) 2001-06-20

Family

ID=24302608

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96119190A Expired - Lifetime EP0780704B1 (en) 1995-12-21 1996-11-29 Plural frequency method and system for identifying metal objects in a background environment

Country Status (5)

Country Link
US (1) US5654638A (en)
EP (1) EP0780704B1 (en)
AU (1) AU701908B2 (en)
CA (1) CA2181430C (en)
DE (1) DE69613455D1 (en)

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US6756783B2 (en) * 1999-06-01 2004-06-29 Merlin Technology, Inc Multi-frequency boring tool locating system and method
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ATE278972T1 (en) * 2000-03-22 2004-10-15 Univ Johns Hopkins ELECTROMAGNETIC SENSOR SYSTEM FOR OBJECT DISCRIMINATION AND METHOD FOR DISCOVERING AND IDENTIFYING METAL OBJECTS
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US6724191B1 (en) * 2000-05-09 2004-04-20 Admiralty Corporation Systems and methods useful for detecting presence and/or location of various materials
GB0023303D0 (en) * 2000-09-22 2000-11-08 Safeline Ltd Metal detector
US20040155651A1 (en) * 2003-02-12 2004-08-12 Britton Andrew Michael Flux control system for metal detectors
US7062414B2 (en) * 2003-07-18 2006-06-13 Metrotech Corporation Method and apparatus for digital detection of electromagnetic signal strength and signal direction in metallic pipes and cables
US7113124B2 (en) 2003-11-25 2006-09-26 Metrotech Corporation, Inc. Centerline and depth locating method for non-metallic buried utility lines
US7834801B2 (en) 2003-11-25 2010-11-16 Metrotech Corporation, Inc. Sensor fusion for model-based detection in pipe and cable locator systems
KR100661313B1 (en) * 2003-12-03 2006-12-27 한국전자통신연구원 Multimedia communication system based on session initiation protocol capable of providing mobility using lifelong number
WO2006015310A2 (en) * 2004-07-29 2006-02-09 Metrotech Corporation, Inc. Sensor fusion for model-based detection in pipe and cable locator systems
WO2006047822A1 (en) * 2004-11-03 2006-05-11 Minelab Electronics Pty Limited Metal detector
WO2007070927A1 (en) * 2005-12-20 2007-06-28 Minelab Electronics Pty Limited Real-time rectangular-wave transmitting metal detector platform with user selectable transmission and reception properties
US20080055080A1 (en) * 2006-07-21 2008-03-06 Andrew Michael Britton Oscillator coil geometry for radio frequency metal detectors
US7667464B2 (en) * 2006-11-02 2010-02-23 Westerngeco L.L.C. Time segmentation of frequencies in controlled source electromagnetic (CSEM) applications
WO2009062230A1 (en) * 2007-11-12 2009-05-22 Minelab Electronics Pty Limited Metal detector with improved magnetic response application
US8749239B2 (en) * 2008-10-02 2014-06-10 Certusview Technologies, Llc Locate apparatus having enhanced features for underground facility locate operations, and associated methods and systems
WO2010133501A1 (en) * 2009-05-18 2010-11-25 Sick Ag A sensor for detecting metal objects
CA2710269C (en) 2009-08-11 2012-05-22 Certusview Technologies, Llc Locating equipment communicatively coupled to or equipped with a mobile/portable device
US8207731B2 (en) * 2009-09-30 2012-06-26 Thermofisher Scientific Apparatus and method for automatic product effect compensation in radio frequency metal detectors
US8729902B1 (en) * 2009-10-05 2014-05-20 White's Electronics, Inc. Metal detector analysis and display methods
EP2439560B1 (en) 2010-10-07 2013-05-29 Mettler-Toledo Safeline Limited Method for monitoring the operation of a metal detection system and metal detection system
EP2439559B1 (en) 2010-10-07 2013-05-29 Mettler-Toledo Safeline Limited Method for operating of a metal detection system and metal detection system
US8587301B2 (en) 2010-10-07 2013-11-19 Mettler-Toledo Safeline Limited Method for operating a metal detection system and metal detection system
CN102411016B (en) * 2011-08-12 2014-06-04 聚能户外用品技术服务(深圳)有限公司 Metal resolution algorithm
US9018935B2 (en) 2011-09-19 2015-04-28 Mettler-Toledo Safeline Limited Method for operating a metal detection apparatus and apparatus
DE102011120920A1 (en) * 2011-12-09 2013-06-13 Benjamin Bochmann Processing device for measurement data of geophysical investigation methods, method for processing measurement data of geophysical investigation methods and geophysical survey system
EP2938443B1 (en) * 2012-12-28 2017-11-15 D.Evolute Forschungs- Und Entwicklungsgesellschaft Method for detecting and classifying electromagnetically detectable objects in a bulk stream
US9733379B2 (en) * 2014-06-19 2017-08-15 Metrotech Corporation Line locator with a metal detector
WO2018237152A1 (en) * 2017-06-23 2018-12-27 First Texas Products, Llc Multi-frequency metal detector
DE102017124407B4 (en) * 2017-10-19 2020-07-02 Minebea Intec Aachen GmbH & Co. KG Process for signal evaluation, evaluation unit and metal detector

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US3986104A (en) * 1976-01-19 1976-10-12 Robert F. Gardiner Dual frequency metal detector system
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JPS5960274A (en) * 1982-09-30 1984-04-06 Anritsu Corp Metal detector
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3686564A (en) * 1970-10-08 1972-08-22 Westinghouse Electric Corp Multiple frequency magnetic field technique for differentiating between classes of metal objects
US3986104A (en) * 1976-01-19 1976-10-12 Robert F. Gardiner Dual frequency metal detector system
US4128803A (en) * 1977-04-29 1978-12-05 Pni, Inc. Metal detector system with ground effect rejection
EP0091034A2 (en) * 1982-04-01 1983-10-12 Asea Ab Arrangement for the detection of metallic objects in a flow of material
JPS5960274A (en) * 1982-09-30 1984-04-06 Anritsu Corp Metal detector
WO1987004801A1 (en) * 1986-02-04 1987-08-13 Minelab Electronic Industries Ltd. Metal detection in conducting media using a two frequency signal

Also Published As

Publication number Publication date
US5654638A (en) 1997-08-05
AU701908B2 (en) 1999-02-11
CA2181430C (en) 1999-12-07
DE69613455D1 (en) 2001-07-26
EP0780704B1 (en) 2001-06-20
EP0780704A2 (en) 1997-06-25
CA2181430A1 (en) 1997-06-22
AU7641096A (en) 1997-06-26

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